This invention relates to a document feeder for use with a photocopying machine.
Semi-automatic document feeders which are fed individual sheets manually, but which position, discharge, and stack such sheets automatically are known in the art. One such feeder of the prior art is designed for use with a copying machine having an upwardly facing glass platen for receiving documents for copying. In this feeder, documents are fed manually face-down to the platen from the front thereof, and are moved by light transport belts backward along the surface of the platen until the leading or rearmost document edge is aligned with the rear edge of the platen. At that time a plurality of fingers extending upwardly along said rear edge of the platen stop the document for copying. The belts are made of low friction material to permit the document to slide relative thereto. When copying is complete, the fingers retract to allow the document to be carried to the rear of the machine to be discharged into a collection tray. Not only does such an arrangement enhance operating convenience, but it also increases the effective copying rate from about 10 copies per minute to a rate of about 20 to 30 copies per minute.
Such machines of the prior art possess several inherent design disadvantages, however. Since the collection tray for the original document is necessarily located in the rear of the machine, the operator must periodically reach back behind the machine to retrieve documents which have been copied. This operation is awkward and inconvenient. Secondly, if a multi-page original is supplied to the feeder last page first in order to cause the copies to be delivered in the proper order, the original pages will be collected in the reverse order and must be rearranged manually.